A plasma processing apparatus is used to perform plasma processing on a substrate. The plasma processing apparatus includes a chamber and a substrate support. The substrate support is provided in the chamber. In the plasma processing apparatus, a process gas is supplied into the chamber and a plasma is formed from the process gas. The substrate is processed by chemical species from the plasma of the process gas.
In the plasma processing, reaction products are generated. The reaction products adhere to a wall surface in the chamber and form deposits. It is necessary to remove the deposits formed on the wall surface in the chamber. Japanese Patent Application Laid-Open Publication No. 2015-170611 discloses a cleaning method for removing deposits formed on a surface of an upper electrode of a capacitively-coupled plasma processing apparatus.